#main{
  width:370px;
  margin:50px auto;
  font-size:1.1em;
}

#calc{
  width:70px;
  margin-left:58px;
}

input,label{
  margin:5px 0
}
span{
  color:red
}
#width-validation,#height-validation{
  color:red;
  margin-left:58px;
  font-size:0.8em
}
